盐渍化灌区不同水肥条件向日葵氮磷利用率及淋失规律

针对内蒙古河套灌区水肥利用率低、土壤盐渍化严重的现状,采用田间试验研究不同处理(常规灌水施肥、节水节氮、常规灌水不施肥)对向日葵产量、株高、生物量、氮肥利用率、磷肥利用率的影响,分析土壤剖面N、P分布情况及田间N、P流失途径、流失量。结果表明,葵花田在当地常规灌水施氮的基础上节氮节水各20%后,向日葵氮的利用率提高了36.15%,流失的氮素显著低于常规灌水施氮处理。因此,试验区具有很大的节氮空间,优化施氮技术应大力推广。氮肥在淋洗过程中大部分会随渗漏液淋失,而磷肥随渗漏液流失量较小。

Nitrogen and Phosphorus Utilization of Sunflower and Loss Under Different Water and Fertilizer Conditions in Salinization of Irrigation Area

Currently,irrigation and fertilizer utilization rate is low and soil salinization is serious in Inner Mongolia.In view of this situation,by using the field experiment method,the effects of different treatment(conventional irrigation fertilization,nitrogen water saving sections,conventional irrigation without fertilization) on sunflower yield,plant height,biomass,the utilization rate of nitrogenous fertilizer and phosphate fertilizer were studied,soil N,P distribution and N,P loss way,loss amount in the field were analyzed.Results show that the sunflower fields in local general nitrogen and water-saving irrigation effects of nitrogen application on the basis of section 20%,sunflower N utilization improved 36.15%,the loss of nitrogen was significantly lower than conventional irrigation N treatment.Therefore,the test area has a great nitrogen saving space and the optimizing nitrogen technology should be promoted.Most of the N fertilizer will be lost with leakage liquid leaching in leaching process,but P fertilizer lost through the leakage with small loss amount.